I feel like the Treadwall--a rock wall on a treadmill-style conveyor belt--might be the ultimate example of something that appears to be really easy, but in practice makes 80% of its users look like complete assholes. Kind of like the mechanical bull. Or smart girls in short skirts. But at least the bouldering belt rotates by body weight alone, meaning that it will automatically match climbers' movements, instead of heaving them to the ground after 12.7 seconds. Or one vodka tonic. The motorless Treadwall also has an adjustable axis for advanced scramblers to increase the difficulty of angles and holds.
Treadwalls are available as both freestanding and wall-mounted units, each measuring 6' x 11'. Components include a freestanding or wall-mounting frame, counter, mat, holds, side covers, textured surfacing, and photo electric sensors.